provide hbbft data by via Prometheus Interface.

[SurfingNerd]

DMDcoin/openethereum-3.x#17

[SurfingNerd]

additions in prometheus code causes thread panics.

     tokio_executor::global::with_default::{{closure}}
             at /home/dmdnode/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-executor-0.1.10/src/global.rs:221:9
      std::thread::local::LocalKey<T>::try_with
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/thread/local.rs:446:16
      std::thread::local::LocalKey<T>::with
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/thread/local.rs:422:9
      tokio_executor::global::with_default
             at /home/dmdnode/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-executor-0.1.10/src/global.rs:190:5
      tokio_threadpool::worker::Worker::do_run::{{closure}}
             at /home/dmdnode/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-threadpool-0.1.18/src/worker/mod.rs:125:13
      std::thread::local::LocalKey<T>::try_with
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/thread/local.rs:446:16
      std::thread::local::LocalKey<T>::with
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/thread/local.rs:422:9
      tokio_threadpool::worker::Worker::do_run
             at /home/dmdnode/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-threadpool-0.1.18/src/worker/mod.rs:116:9
      tokio_threadpool::pool::Pool::spawn_thread::{{closure}}
             at /home/dmdnode/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-threadpool-0.1.18/src/pool/mod.rs:345:21
      std::sys_common::backtrace::__rust_begin_short_backtrace
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/sys_common/backtrace.rs:121:18
  22: std::thread::Builder::spawn_unchecked_::{{closure}}::{{closure}}
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/thread/mod.rs:558:17
      <core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/core/src/panic/unwind_safe.rs:271:9
      std::panicking::try::do_call
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/panicking.rs:483:40
      std::panicking::try
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/panicking.rs:447:19
      std::panic::catch_unwind
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/panic.rs:140:14
      std::thread::Builder::spawn_unchecked_::{{closure}}
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/thread/mod.rs:557:30
      core::ops::function::FnOnce::call_once{{vtable.shim}}
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/core/src/ops/function.rs:250:5
  23: <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/alloc/src/boxed.rs:1988:9
      <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/alloc/src/boxed.rs:1988:9
      std::sys::unix::thread::Thread::new::thread_start
             at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/sys/unix/thread.rs:108:17
  24: start_thread
  25: clone


Thread 'tokio-runtime-worker-3' panicked at 'name and help must be non-empty: Msg("'NodeId(0x3e4b…c349)_cumulative_lateness' is not a valid metric name")', crates/util/stats/src/lib.rs:65